Odd QIC-like tape

[Tony Duell]

> I'm a bit confused by all those QIC designations,  since they sometimes s=
> eem=20
> to refer to completely different things...

The vearious QIC standards define certain aspects of QIC (Quarter Inch 
Cartridge) tapes.

Some of them, like QIC11 and QIC24 define the way data is to be recorded 
on the tape, the track positions, and so on.

Others, like QIC02 and QIC36 describre the interfaces on the tape drives 
themselves.There are basically 2 classes of interface, the 'raw' 
interface (for example QIC36), where you essentially have the bitstream 
to/from the hard on the interface connector (a bit like a floppy drive 
interface in conceopt) and 'formatted' interfaces, like QIC02 where you 
send 8-bit bytes to the drive, it buffers them, and writes blocks to the 
tape (a bit like SCSI in concept).

> 
> Got one drive here that has a 50-pin connector,  and it came along with a=
> n=20
> 8-bit ISA card -- some sort of a proprietary interface,  and I have no id=

I would guess thati's QIC36, but it could be QIC02. If there's a lot of 
logic on the ISA card, including RAM, it's likely to be a raw interface. 
If the ISA card is little more than an address decoder and 
latches/buffers, then it's a foramtteed interface, and there'll be more 
logic in the drive iteslf.

There were formatter boards that, for example, connected to a 'raw' drive 
on one side (say QIC 36) and provided a fromatted host interface on the 
other (like QIC02). The Archive Sidewinder on my PERQ is like that -- the 
thing is the size of an 8" floppy drive, the drive itself mounts at the 
front of the frame and has a QIC36 interface. It links to a pair of 
stached PCBs bolted ot the frame behind the drive, there's a QIC02 host 
interface on the back.

-tony